Roller reamer with mechanical face seal

ABSTRACT

At least one mechanical face seal is disposed within a cutter cartridge of a roller reamer. The cutter cartridge includes a roller cutter and a retention assembly. A bearing shaft of the retention assembly extends through an inner channel of the roller cutter. A first mechanical face seal is disposed or shared between the roller cutter and a first pillow block of the retention assembly. An optional second mechanical face seal is disposed or shared between the roller cutter and a second pillow block of the retention assembly. Each pillow block is rotatably coupled at an opposing end of the bearing shaft. The retention assembly includes two separately matched sets of one pillow block and a wedge. The wedges in combination detachably secure the pillow blocks to a tool body of the roller reamer.

FIELD OF THE INVENTION

The present invention relates generally to underground boring and, inparticular, to a reamer assembly for enlarging or maintaining aclearance diameter of an existing borehole. More particularly, thepresent invention relates to roller reamers having roller cutterrotatably coupled with roller reamer tool bodies.

BACKGROUND OF THE INVENTION

The subject matter discussed in the background section should not beassumed to be prior art merely as a result of its mention in thebackground section. Similarly, a problem mentioned in the backgroundsection or associated with the subject matter of the background sectionshould not be assumed to have been previously recognized in the priorart. The subject matter in the background section merely representsdifferent approaches, which in and of themselves may also be inventions.

It is often necessary when drilling a borehole to maintain or enlargethe diameter of the borehole with second and subsequent passes ofcutting components. This is necessary due to drill bit wear and gradualreduction in the gauge diameter of the hole. Also, certain materialsbeing drilled can swell, which results in reduction of the boreholediameter after the drill bit has past.

The technique of reaming is a significant step in achieving the requireddiameter of the borehole. Accordingly, there is a long-felt need forreamers presenting improved reliability, construction and longevity anddecreased maintenance requirements.

Reamers can be used in association with a drill bit to ensure that aborehole is drilled to a constant diameter. A roller-type reamer hascutting components rotatably mounted. The roller reamer is commonly usedin the drilling industry, one purpose being to ream the hole just behindthe drill bit to maintain hole size. A roller reamer can also act as astabilizer above the drill bit to stabilize the drill bit and drillstring against the deviating tendencies encountered during drilling.

Roller reamer roller assemblies that include roller cutters aregenerally intended to be coupled with a reamer body, or tool body, whileallowing the roller cutters to freely rotate about an axis that isparallel with a central axis of the tool body. One problem with rollerreamers is that under the conditions commonly encountered duringdrilling, rock chips and other debris can build up proximate to one ormore roller assemblies, which may jam or slow rotation of the rollerassemblies, thereby reducing their effectiveness. Also, even undernormal operating conditions, rotation of the roller cutters can alsocause a roller assembly to increase in temperature which furtherincreases the stress on the rotating parts. Increased stress may causethose rotating parts to wear more quickly. This is a costly problembecause the reamer will have to be brought to the surface, dismantledand reassembled.

It is an object of the present invention to provide a useful alternativemeans to seal a roller cutter from external debris of a borehole andthereby improve reliability and performance of the roller reamer.

SUMMARY AND OBJECTS OF THE INVENTION

Towards these and other objects of the present invention (hereinafter,“the invented roller reamer”) that are made obvious to one of ordinaryskill in the art in light of the present disclosure, an invented rollerreamer is providing having at least one mechanical face seal disposedwithin a roller assembly that is coupled with a tool body. A retentionassembly is detachably attached to a roller cutter of the rollerassembly to form a cutter cartridge. Each of two sections of theretention assembly include a pillow block, wherein each pillow block isdetachably positioned at opposing ends of the roller cutter. Eachretention assembly section further includes a wedge that enables secureand detachable retention of the cutter cartridge into an axial recess ofthe tool body.

In one optional aspect of the invented roller reamer, a bearing shaft ofthe cutter cartridge extends wholly through a cavity of the rollerassembly and is fixedly coupled at opposing ends to respective pillowblocks. The bearing shaft captures the roller assembly. An outer half ofa first mechanical face seal is coupled with a first pillow block of afirst section of the retention assembly and an inner half of the firstmechanical face seal is coupled with at a first end of the rollerassembly.

The first mechanical face seal includes an outer seal ring, an outerenergizer, an inner seal ring and an inner energizer. The outerenergizer is disposed under compression between the first pillow blockand the outer seal ring. The outer energizer presses the outer seal ringagainst the inner seal ring. The inner energizer is disposed undercompression between the roller cutter and the inner seal ring. The innerenergizer presses the inner seal ring against the outer seal ring.

In another optional aspect of the invented roller reamer, another outerhalf of a second mechanical face seal is coupled with a second pillowblock of a second section of the retention assembly and another innerhalf of the second mechanical face seal is coupled at a second end ofthe roller assembly.

The second mechanical face seal includes a second outer seal ring, asecond outer energizer, a second inner seal ring and a second innerenergizer. The second outer energizer is disposed under compressionbetween the second pillow block and the second outer seal ring.

Certain alternate preferred embodiments of the invented roller reamerinclude two or more cutter cartridges coupled with a same tool body,wherein one or more mechanical face seals are separately disposedbetween pillow blocks and cutter assemblies.

More particularly, certain other alternate preferred embodiments of theinvented reamer include three cutter cartridges coupled with analternative tool body, wherein a separate mechanical face seal isdisposed between each pillow block thereof and the attached rollercutter. Certain additional alternate preferred embodiments of theinvented reamer include six cutter cartridges coupled with anotheralternative tool body, wherein a separate mechanical face seal isdisposed between each pillow block thereof and the attached rollercutter.

Certain yet other alternate preferred embodiments of the invented reameroptionally include one or more of the features of: (a.) a plurality ofball bearings disposed within a race positioned about and circling thebearing shaft in a plane normal to the central tool axis; (b.) aplurality of cutting inserts positioned along an outer surface of theroller cutter; (c.) at least one cutting insert of the roller cutterhaving a central depression extending toward the central tool axis; (d.)at least one cutting insert of the roller cutter comprising tungstencarbide; and (e.) at least one cutting insert of the roller cuttercomprising polycrystalline diamond.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

INCORPORATION BY REFERENCE

The present disclosure incorporates by reference the two previouslyfiled US Nonprovisional Patent Applications, in their entirety and forall purposes, of U.S. Nonprovisional patent application Ser. No.15/456,415, filed on Mar. 10, 2017, and titled REAMER FOR USE INDRILLING OPERATIONS; and U.S. Nonprovisional patent application Ser. No.15/387,875 filed on Dec. 22, 2016 and titled REAMER CUTTING INSERT FORUSE IN DRILLING OPERATIONS.

BRIEF DESCRIPTION OF THE FIGURES

The detailed description of some embodiments of the invention is madebelow with reference to the accompanying figures, wherein like numeralsrepresent corresponding parts of the figures.

FIG. 1A is a side perspective view of a first preferred embodiment ofthe present invention (hereinafter, “first roller reamer”) having threeinvented roller assemblies rotatably coupled within separate andindividual axial recesses of a same tool body;

FIG. 1B is a top view cut-away view of the first roller reamer of FIG.1A having three invented roller assemblies rotatably coupled withinseparate and individual axial recesses of the tool body of FIG. 1A;

FIG. 2 is a side view of an exemplary roller assembly of FIG. 1Ainserted into an exemplary axial recess of the tool body of FIG. 1A androtatably coupled with a pair of pillow blocks of a first retentionassembly;

FIG. 3 is an exploded detailed side view of the exemplary first rollerassembly of FIG. 2 and elements of the cutter cartridge of FIG. 2;

FIG. 4A is a cut-away detailed side view of a first invented mechanicalface seal of FIG. 3 disposed between a first end of the first rollerassembly of FIG. 2 and the first pillow block of FIG. 2;

FIG. 4B is a cut-away detailed side view of a second invented mechanicalface seal of FIG. 3 disposed between a second end of the first rollerassembly of FIG. 2 and the second pillow block of FIG. 2;

FIG. 5 is a partial cut-away perspective view of the exemplary firstmechanical face seal of FIG. 3;

FIG. 6 is an exploded perspective view of the exemplary first mechanicalface seal of FIG. 3;

FIG. 7 is an exploded perspective view of the exemplary secondmechanical face seal of FIG. 3;

FIG. 8 is an exploded detailed side view of the exemplary first rollerassembly of FIG. 2 and showing three additional shaft bushings; and

FIG. 9 is a top view cut-away view of a second invented roller reamerhaving three additional invented roller assemblies of FIG. 1A detachablycoupled with an alternate tool body, wherein alternate tool bodyprovides a total of six axial recess and the second invented rollerreamer includes six roller assemblies of FIG. 1A.

DETAILED DESCRIPTION

In the following detailed description of the invention, numerousdetails, examples, and embodiments of the invention are described.However, it will be clear and apparent to one skilled in the art thatthe invention is not limited to the embodiments set forth and that theinvention can be adapted for any of several applications.

It is understood that the word “exemplary” is used herein to mean“serving as an example, instance, or illustration.” Any aspect describedherein as “exemplary” is not necessarily to be construed as exclusive,preferred or advantageous over other aspects.

It is to be understood that this invention is not limited to particularaspects of the present invention described, as such may, of course,vary. It is also to be understood that the terminology used herein isfor the purpose of describing particular aspects only, and is notintended to be limiting, since the scope of the present invention willbe limited only by the appended claims. Methods recited herein may becarried out in any order of the recited events which is logicallypossible, as well as the recited order of events.

Where a range of values is provided herein, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range, is encompassed within the invention. The upper and lowerlimits of these smaller ranges may independently be included in thesmaller ranges and are also encompassed within the invention, subject toany specifically excluded limit in the stated range. Where the statedrange includes one or both of the limits ranges excluding either or bothof those included limits are also included in the invention.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present invention, the methodsand materials are now described.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include plural referents unless thecontext clearly dictates otherwise. It is further noted that the claimsmay be drafted to exclude any optional element. As such, this statementis intended to serve as antecedent basis for use of such exclusiveterminology as “solely,” “only” and the like in connection with therecitation of claim elements, or use of a “negative” limitation.

Referring now generally to the Figures particularly to FIG. 1A and FIG.1B, FIG. 1A is a top view of a first preferred embodiment of theinvented roller reamer 100 (hereinafter, “the first reamer” 100) havingthree roller assemblies 102, 104 & 106 rotatably and removably coupledwithin separate and individual axial recesses 108A, 108B & 108C (asshown in FIG. 1B) of a tool body 110. A central tool axis A of the toolbody 110 (hereinafter, “the tool axis A”) extends centrally to the firstinvented roller assembly 102 along an elongate dimension of the toolbody 110. For the sake of clarity of explanation the means of retainingof each individual cutter cartridge 112 of each of the three rollerassemblies 102, 104 & 106 within the individual axial recesses of thetool body 110 are not presented fully in either FIG. 1A or FIG. 1B andare disclosed in detail at least in the text accompanying FIGS. 3, 4Aand 4B. Each roller assembly 102, 104 & 106 includes a plurality ofcutting inserts 114. One or more of the cutting inserts of the pluralityof cutting inserts 114 may be or comprise tungsten carbide,polycrystalline diamond, or other suitable abrasive material known inthe art.

Referring now generally to the Figures particularly to FIG. 2, FIG. 2 isa side view of the first exemplary invented roller assembly 102 of FIG.1A (hereinafter, “the first roller assembly” 102) inserted into thefirst exemplary axial recess 108A of the tool body 110 of FIG. 1A. Apair of pillow blocks 200A & 200B are rotatably coupled with the firstroller assembly 102. A first pillow block 200A is positioned at a firstend 202A the first roller assembly 102. A first wedge 204A is removablycoupled to the tool body 110 by a first bolt 206A.

A second pillow block 200B is positioned at a second end 202B of thefirst roller assembly 102. A second wedge 204B is removably coupled by asecond bolt 206B to the tool body 110. The first wedge 204A and thesecond wedge 204B are sized and shaped to be respectively detachablyattached by the bolts 206A & 206B to the tool body 110 to retain thepair of pillow blocks 200A & 200B and the first roller assembly 102within the first axial recess 108A when the pair of pillow blocks 200A &200B with the first roller assembly 102 are rotatably and detachablycoupled. The pair of wedges 204A & 204B are sized and shaped to lockeach respective pillow block pillow block 200A & 200B and coupled firstroller assembly 102 in the axial and radial directions within the firstaxial recess 108A.

A second plurality of cutting inserts 208 are positioned on an externalside the pillow blocks 200A & 200B, and a third plurality of cuttinginserts 210 are positioned on an external side of the tool body 110. Oneor more of the cutting inserts of the second plurality of cuttinginserts 208 or third plurality of cutting inserts 210 may be or comprisetungsten carbide, polycrystalline diamond, or other suitable abrasivematerial known in the art.

Referring now generally to the Figures particularly to FIG. 3, FIG. 3 isan exploded detailed side view of the cutter cartridge 112 of the firstroller assembly 102 and elements of an exemplary first retentionassembly 300. The first retention assembly 300 of the first rollerassembly 102 includes the pair of pillow blocks 200A & 200B, the firstwedge 204A and the second wedge 204B, a bearing shaft 302, a pluralityof ball bearings 304, and two static O-ring shaft seals 306A & 306B. Thebearing shaft 302 is fixedly coupled to the pair of pillow blocks 200A &200B by pins (not shown) and is shaped from a first shaft seal groove308A, a second shaft seal groove 308B and a shaft race 310. The firstshaft seal groove 308A is sized and shaped to seat the a first staticO-ring shaft seal 306A while a first roller cutter 312 of the firstroller assembly 102 is positioned about the bearing shaft 302 and thebearing shaft 302 is coupled to the pair of pillow blocks 202A& 202B.The shaft race 310 is also sized and shaped to seat the plurality ofball bearings 304 while the first roller cutter 312 is positioned aboutthe bearing shaft 302 and the bearing shaft 302 is coupled to the pairof pillow blocks 202A & 202B.

It is understood that a key function of the faces seals 314 & 316 is tokeep external debris 318 from polluting a volume between of the rollercutter 312 and the bearing shaft 302.

FIG. 3 further presents an exemplary first mechanical face seal 314, anexemplary second mechanical face seal 316 and the first roller cutter312. The first roller cutter 312 is comprised with the first rollerassembly 102 and includes the plurality of cutting inserts 114. Thefirst mechanical face seal 314, and the second mechanical face seal 316sized and shaped to fit operationally around the bearing shaft 302,within an internal channel 320 of the first roller cutter 312 (as shownin FIGS. 4A and 4B) and partly within each of the pillow blocks 200A &200B.

Referring now generally to the Figures particularly to FIG. 4A and FIG.4B, the first mechanical face seal 314 (hereinafter, “the first faceseal” 314) is coupled in part to the first pillow block 200A and isadditionally coupled in part to the first roller assembly 102 at thefirst end 202A, and the second mechanical face seal 316 (hereinafter,“the second face seal” 31) is coupled in part to the second pillow block200B and is additionally coupled in part to the first roller assembly102 at the second end 202B.

Referring now generally to the Figures particularly to FIG. 4A, FIG. 4Ais a cut-away detailed side view of the first face seal 314 as it ispreferably disposed in part within both the first end 202A of the firstroller assembly 102 and the first pillow block 200A. The firstmechanical face seal 314 comprises a first outer energizer 400, a firstouter seal ring 402, a first inner seal ring 404 and a first innerenergizer 406. The first outer seal ring 402 is pressed against thefirst inner seal ring 404 by force received from the first outerenergizer 400. It is understood that first pillow block 200A and theroller cutter 312 in combination present a first seal recess 407 whichthe first outer energizer 400 and the first inner energizer 406 of thefirst seal 314 rest.

It is understood that in operation of the invented reamer in a boreholethat the first outer seal ring 402 and the first inner seal ring 406 arepressed together by the first outer energizer 400 and the first innerenergizer 404.

The first inner seal ring 404 is sized and shaped to fit within firstroller cutter 312; the first inner energizer 406 is captured between thefirst roller cutter 312 and the first inner seal ring 404. The firstinner seal ring 404 is pressed against the first outer seal ring 402 byforce received from the first inner energizer 406.

The first outer seal ring 402 is sized and shaped to encircle thebearing shaft 302 in a plane normal to the tool axis A while displacedfrom contact with the bearing shaft 302;

the first inner seal ring 404 is sized and shaped to encircle thebearing shaft 302 in a plane normal to the tool axis A while optimallydisplaced from contact with the bearing shaft 302 by the volume oflubricant 408.

More generally, the first roller assembly 102 is optimally designed tomaintain the outer and inner circumferences of several elements withinplanes normal the tool axis A while the first roller assembly 102 isassembled and positioned for operation within the first recess 108A, toinclude the static O-ring shaft seals 306A & 306B, the plurality of ballbearings 304, the first face seal 314 and the second face seal 316. Itis noted that an upper race feature 410 of the roller cutter 312 isshaped, sized and positioned within the first roller cutter 312 to actin combination with the ball bearing race 310 of the bearing shaft 302to maintain the plurality of ball bearings 304 in an operationalorientation within a plane that is normal the elongate axis A; theplurality of ball bearings 304 help maintain a rotatable coupling of thebearing shaft 302 and the first roller cutter 312 while the plurality ofball bearings 304 are simultaneously seated in both the ball bearingrace 310 of the bearing shaft 302 and the upper race feature 410 of theroller cutter 312 and thereby positioned within a plane that is normalthe elongate axis A. The ball bearing races 310 & 410 and the ballbearings 304 lock the bearing shaft 302 within the cutter cartridge 112and allow rotation of the roller cutter 312 about the bearing shaft 302,but prevent axial movement of the roller cutter 312 along the bearingshaft 302.

It is understood that a shaft step 412 of the bearing shaft 302uniformly encircles the tool axis A and is disposed between the firstmechanical seal 314 and a first shaft bushing 414. The bearing shaftstep 412 forms the ball bearing race 310 and is shaped, sized andpositioned to inhibit the first shaft bushing 414 from moving in thedirection of the first pillow block 200A along the tool axis A.

Referring now generally to the Figures particularly to FIG. 4B, FIG. 4Bis a cut-away detailed side view of the second face seal 316 disposedbetween the first cutter roller 312 and the second pillow block 200B.The second face seal 316 is sized and shaped to simultaneously fitwithin both the second pillow block 200B and within the first rollercutter 312 at the second end 202B of the first roller assembly 102.

The second face seal 316 comprises a second inner energizer 416, asecond inner seal ring 418, a second outer seal ring 420 and a secondouter energizer 422. It is understood that second pillow block 200B andthe cutter cartridge 112 in combination present a second seal recess 423which the second outer energizer 422 and the second inner energizer 416of the first seal 316 rest.

It is understood that in operation of the invented reamer in a boreholethat the second outer seal ring 420 and the second inner seal ring 418are pressed together by the second outer energizer 422 and the secondinner energizer 416.

The second inner seal ring 418 is sized and shaped to fit within thefirst roller cutter 312;

the second inner energizer 416 is captured between the first rollercutter 312 and the second inner seal ring 418. The second inner sealring 418 is pressed against the second outer seal ring 420 by forcereceived from the second inner energizer 416.

The first outer seal ring 402, first inner seal ring 404, second innerseal ring 418 and/or the second outer seal ring 420 may be or compriseCarbon, Ceramic, Ni-resist, 17-4, Silicon Carbide, Tungsten Carbide, aCast Iron Alloy, graphite filled Polytetrafluoroethylene, and/orsuitable materials coatings, coated surfaces known in the art, toinclude plasma coatings that comprise silicon or tungsten carbidesprayed onto a stainless steel seal head. The first outer energizer 400,the first inner energizer 406, the second inner 416 & second outerenergizer 422 may be or comprise an elastomer and/or other suitablematerial known in the art.

The second outer seal ring 420 is sized, shaped and positioned withinthe first roller assembly 102 to encircle the bearing shaft 302 in aplane normal to the tool axis A while optimally displaced from contactwith the bearing shaft 302 by a volume of lubricant 408; the secondinner seal ring 418 is sized, shaped and positioned within the firstroller assembly 102 to encircle the bearing shaft 302 in a plane normalto the tool axis A while optimally displaced from contact with thebearing shaft 302 by the volume of lubricant 408. Both the second innerenergizer 416 and the second outer energizer 422 are sized, shaped andpositioned within the first roller assembly 102 to encircle the bearingshaft 302 in a plane normal to the tool axis A.

It is again noted that the second shaft seal groove 308B of the bearingshaft 302 is optimally shaped, sized and positioned to maintain bothouter and inner circumferences of the second static O-ring shaft seal306B to encircle the bearing shaft 302 while the second static O-ringshaft seal 306B is positioned within a plane normal to the tool axis A.

It is understood that a roller cutter step 424 of the roller cutter 312uniformly encircles the tool axis A and is disposed between the secondmechanical seal 316 and a second shaft bushing 426. The roller cutterstep 424 is shaped, sized and positioned to inhibit the second shaftbushing 426 from moving in the direction of the second pillow block 200Balong the tool axis A. The second shaft bushing 426 is free to rotateabout the bearing shaft 302 while captured between the bearing shaft 302and the first roller cutter 312 in accordance with forces directed byand/or transferred through the lubricant 408, the bearing shaft 302 andthe first roller cutter 312.

Referring now generally to the Figures particularly to FIG. 5, FIG. 5 isa partial cut-away perspective view of the exemplary first mechanicalface seal 314. As disclosed in FIG. 4A and FIG. 4B, the first outerenergizer 400 and the first outer seal ring 402 of the first mechanicalface seal 314 are coupled with the first pillow block 200A, and thefirst inner energizer 406 and the first inner seal ring 404 of the firstmechanical face seal 314 is coupled with the first roller cutter 312 atthe first end 202A of the first roller assembly 102.

Referring now generally to the Figures particularly to FIG. 6, FIG. 6 isan exploded perspective view of the first outer energizer 400 and thefirst outer seal ring 402 of the first face seal 314. It is understoodthat the outer energizer 400 and the outer seal ring 402 are eachcircular within a plane normal to the tool axis A when the first faceseal 314 is installed in the configuration of FIG. 2.

Referring now generally to the Figures particularly to FIG. 7, FIG. 7 isan exploded perspective view of the first inner energizer 406 and thefirst inner seal ring 404 of the first face seal 314. It is understoodthat the first inner energizer 406 and the first inner seal ring 404 areeach circular within a plane normal to the tool axis A when the firstface seal 314 is installed in the configuration of FIG. 2.

Referring now generally to the Figures particularly to FIG. 8, FIG. 8 isan exploded detailed side view of the first roller assembly 102 andshowing a third shaft bushing 800 positioned between the first shaftbushing 414 and the second shaft bushing 426. The third shaft bushing800 is sized, shaped and positioned within the operationally assembledfirst roller assembly 102 to encircle the shaft 302. The first shaftbushing 414 and the second shaft bushing 426 respectively limit theaxial degree of movement of the third shaft bushing 800 (a.) toward thefirst pillow block 200A, and (b.) toward the second pillow block 200B.

Referring now generally to the Figures particularly to FIGS. 1A, 1B, 3,4A, 4B and 8, it is understood that the cutter cartridge 112 may includeor comprise the roller cutter 312, the bearing shaft 302, the threeshaft bushings 414, 426 & 800, the two wedge bolts 206A& 206B, the pairof pillow blocks 200A & 200B, the pair of shaft seal O-rings 306A &306B, the plurality of ball bearings 304, two or more pins (not shown)that respectively attach the bearing shaft 302 to the separate pillowblocks 200A & 200B, and/or the two face seals 314 & 316.

Referring now generally to the Figures particularly to FIGS. 2, 3 and 8,it is disclosed in the present Application for patent that the firstretention system 300 comprises the bearing shaft 302, the three shaftbushings 414, 426 & 800, the pair of wedges 204A & 204B, the two wedgebolts 206A& 206B, the pair of pillow blocks 200A & 200B, the pair ofshaft seal O-rings 306A & 306B, the plurality of ball bearings 304, andtwo or more pins (not shown) that respectively attach the bearing shaft302 to the separate pillow blocks 200A & 200B. It is understood that theretention system 300 may optionally comprise or merely be coupled withthe first outer energizer 400, the first outer seal ring 402, the secondouter energizer 422 and/or the second outer seal ring 420. It isunderstood that the three shaft bushings 414, 426 & 800 could bereformulated as one continuous or two complementary shaft bushings.

Referring now generally to the Figures particularly to FIG. 9, FIG. 9 isa top cut-away view of a second invented roller reamer 900 having threeadditional invented roller assemblies 102 that are each separately,detachably and respectively coupled within separate and individual axialrecesses 108D, 108E & 108F of an alternate tool body 902. It isunderstood the second invented roller assembly 104, the third inventedroller assembly 106 and each of the additional roller assemblies 102 maypresent, include and/or be adapted to cooperate, engage and/or becoupled directly or indirectly with any and/or all aspects, componentsand/or elements 110-800 of the first roller assembly 102 or the cuttercartridge 112 as disclosed herein.

In understanding the scope of the present invention, the term“comprising” and its derivatives, as used herein, are intended to beopen ended terms that specify the presence of the stated features,elements, components, groups, integers, and/or steps, but do not excludethe presence of other unstated features, elements, components, groups,integers and/or steps. The foregoing also applies to words havingsimilar meanings such as the terms, “including”, “having” and theirderivatives. Also, the terms “part,” “section,” “portion,” “member” or“element” when used in the singular can have the dual meaning of asingle part or a plurality of parts. Finally, terms of degree such as“substantially”, “about” and “approximately” as used herein mean areasonable amount of deviation of the modified term such that the endresult is not significantly changed.

While selected embodiments have been chosen to illustrate the inventedsystem, it will be apparent to those skilled in the art from thisdisclosure that various changes and modifications can be made hereinwithout departing from the scope of the invention as defined in theappended claims. For example, the size, shape, location or orientationof the various components can be changed as needed and/or desired.Components that are shown directly connected or contacting each othercan have intermediate structures disposed between them. The functions ofone element can be performed by two, and vice versa. The structures andfunctions of one embodiment can be adopted in another embodiment, it isnot necessary for all advantages to be present in a particularembodiment at the same time. Every feature which is unique from theprior art, alone or in combination with other features, also should beconsidered a separate description of further inventions by theapplicant, including the structural and/or functional concepts embodiedby such feature(s). Thus, the foregoing descriptions of the embodimentsaccording to the present invention are provided for illustration only,and not for the purpose of limiting the invention as defined by theappended claims and their equivalents.

I claim:
 1. A roller reamer comprising: a tool body having at least oneaxial recess; a roller assembly comprising a roller cutter and aretention assembly removably positioned with the at least one axialrecess, wherein the roller cutter is rotatably coupled with theretention assembly; and a first mechanical face seal disposed betweenthe retention assembly and roller cutter, wherein an inner seal ring ofthe first mechanical face seal is coupled with the roller cutter at afirst end of the roller cutter and an outer seal ring of the mechanicalface seal is coupled with the retention assembly.
 2. The roller reamerof claim 1, wherein the retention assembly comprises a pillow block anda bearing shaft, wherein the pillow block is removably coupled with thetool body and the bearing shaft, and the bearing shaft extends throughthe roller cutter.
 3. The roller reamer of claim 2, wherein theretention assembly further comprises a wedge, the wedge adapted todetachably and fixedly couple the pillow block with the tool body. 4.The roller reamer of claim 2, wherein the bearing shaft extends fullythrough the roller cutter in parallel with a central axis of the toolbody.
 5. The roller reamer of claim 2, further comprising a secondmechanical face seal positioned proximal to an opposing end of theroller cutter from the first end of the roller cutter.
 6. The rollerreamer of claim 5, wherein the second mechanical face seal is disposedbetween the retention assembly and the roller cutter, wherein a secondinner seal ring of the second mechanical face seal is coupled with theroller cutter at the second end of the roller cutter and a second outerseal ring of the second mechanical face seal is coupled with theretention assembly.
 7. The roller reamer of claim 6, wherein theretention assembly further comprises a second pillow block and thesecond pillow block is removably coupled with the tool body and fixedlycoupled with the bearing shaft and the second outer seal ring.
 8. Theroller reamer of claim 7, wherein the retention assembly furthercomprises a second wedge, the second wedge adapted to detachably andfixedly couple the second pillow block with the tool body.
 9. The rollerreamer of claim 7, wherein the bearing shaft extends fully through theroller cutter in parallel with a central axis of the tool body.
 10. Theroller reamer of claim 1, wherein the roller cutter comprises at leastone cutting insert.
 11. The roller reamer of claim 10, wherein theroller cutter comprises a plurality of cutting inserts.
 12. The rollerreamer of claim 10, wherein at least one cutting insert of the pluralityof cutting inserts comprises tungsten carbide.
 13. The roller reamer ofclaim 1, wherein the retention assembly comprises a plurality of cuttinginserts.
 14. The roller reamer of claim 1, wherein the tool bodycomprises a plurality of cutting inserts.
 15. The roller reamer of claim2, wherein the pillow block comprises a plurality of cutting inserts.16. The roller reamer of claim 2, wherein the retention assemblycomprises a plurality of cutting inserts.
 17. The roller reamer of claim1, further comprising: a plurality of axial recesses of the tool body; aplurality of cutter cartridges, each cutter cartridge detachably coupledwith a unique recess of the plurality of axial recesses, and each cuttercartridge comprising a retention assembly rotatably coupled with aroller cutter and at least one mechanical face seal disposed between theretention assembly rotatably coupled with the roller cutter of thecomprising cutter cartridge.
 18. The roller reamer of claim 17, whereineach retention assembly comprises a bearing shaft extending through thecoupled roller cutter in parallel with a central axis of the tool body.19. The roller reamer of claim 18, wherein each retention assemblycomprises a pair of pillow blocks fixedly attached to the bearing shaftat opposing ends of the bearing shaft.
 20. The roller reamer of claim19, wherein each retention assembly comprises a pair of wedges adaptedto in combination detachably couple the pair of pillow blocks of thecomprising retention assembly with the tool body.